1. Field of the Invention
The invention relates to storage cells and to devices, including storage batteries which incorporate such cells.
2. Description of Prior Art
The invention relates particularly to rechargeable storage cells that are generally well-known but suffer a major disadvantage of requiring a relatively long charging up time. The invention relates more particularly to electrodes and storage cells of the kind described in U.S. Pat. No. 4,143,216 which comprises a lead-acid storage cell which can be charged more quickly due to its provision of a crystalline active mass electrode material.
It is an object of the invention to provide an improved active mass useful for electrodes in storage cells and methods of producing such active masses.
According to the invention there is provided a composition of matter useful as an active mass of positive electrodes in storage cells, said composition consisting of crystalline lead dioxide (PbO2) having an X-ray diffraction pattern substantially as shown in FIG. 1.
The composition may include trace amounts of cadmium.
The composition may be formed by electrolysis using a lead-cadmium electrode, an electrolyte of dilute sulfuric acid, and pulsed current.
The lead-cadmium electrode may be formed by electrolytic deposition using an electrolyte comprising lead methanesulfonate, cadmium methanesulfonate and methanesulfonic acid, and pulsed current.
The invention may provide a porous lead material for negative electrodes in storage cells formed, using the lead dioxide composition, by electrolytic conversion in dilute sulfuric acid and applying pulsed current.
The invention may provide various compositions of matter useful as an active mass for electrodes in lead acid storage cells formed from electrodeposition using a methanesulfonic acid electrolyte system and pulsed current.